---
title: Federated Clusters
---
<h2>{{ page.title }}</h2>

<p>
  Heroic has support for federating requests, which allows multiple independent
  clusters to serve clients through a single, global interface.
</p>

<p>
  In a federated cluster, requests are routed to <em>shards</em>, and each
  shard is responsible for a distinct chunk of the available data.
  If all nodes in a single shard become unavailable, the data for that shard is
  unavailable.
  Shards are identified by a set of tags, two nodes are said to belong to the
  same shard if their cluster tags are identical. You can see more about this
  in the <a href="config#cluster_config">cluster documentation</a>.
</p>

{% include federation-tail.html %}
